Ductility enhancement in Mg–8.7Gd–4.18Y–0.42Zr magnesium alloy fabricated through extrusion and equal channel angular pressing (EX-ECAP)

The goal of this article was to analyze the microstructural, texture development, deformation mode, and mechanical properties of a Mg–8.7Gd–4.18Y–0.42Zr (wt%) magnesium alloy that underwent conventional extrusion in conjunction with equal channel angular pressing (EX-ECAP) deformation. The findings indicate that as-extruded alloy reveals a significant basal texture, while the ECAPed GW94K alloy demonstrates basal poles that are inclined ~ 45° from the extrusion direction. After 4p-ECAP process at 370 °C via the Bc path, the microstructure of the alloy exhibits a high level of uniformity, with a fine grain area fraction of 92.7% and an average grain size of 3 μm. The GW94K alloy experiences a significant increase in elongation when the ECAP pass is increased, although the ultimate tensile strength (UTS) decreases remarkably. In particular, the sample subjected to ECAP demonstrates a room-temperature tensile elongation of 36.8% in the extrusion direction. This phenomenon can be ascribed primarily to the evolution of the texture during repeated ECAP processes, leading to the activation of multiple deformation modes in ECAP deformation process of the GW94K alloy. Furthermore, the results suggest that the presence of multiple slip systems, characterized by their high Schmid factor and IGMA analyses, significantly influences the uniform elongation.